Electron-tube circuits



Dec 16, 1930. M. VON ARDENNE ET AL ELECTRQN TUBE CIRCUITS Filed Nov.

INVENTOR MANFRED VON ARDENNE BY EINR a 5mm K/CAQ TTORNEY Patented Dec. 16, 1930 PATENT 01 F163 'MANFRED voN aannnnn Ann HEINRICH i-rnrnnnr, or BERLIN, GERMANY, AssIeNons T RADIO oonronarron or AMERICA, A CORPORATION or DELAWARE 1 ntncraonaunn moms,

' Application filed November 13, 1926, Serial No. 1 48,1G6,and in Germany nugust 2j5 I925.

Application filed in Germany, August 25, 1925.

This invention relates to electron tube circuits, and more particularly to aresistance ternative is the use of a damping resistance,

and this has already been suggested in connection with ultra-audion circuits. In such cases the resistance is inserted directly in the radio frequency path.

It is an object of our invention to stabilize a regenerative circuit against. oscillation by the use of a resistance, without that resistance necessarily being in series opposition to the high frequency energy. To this end we place the resistance in parallel with the feedback coil, and more specifically, we prefer to 7 use a three point connection for the regen- .erative coupling. 1 I

It is a further object of our invention to combine a stage of amplification with a re generative circuit in a simple manner which utilizes a single resistance as the coupling re sistance and as the stabilizing resistance.

Other objects will appear in the specification and claims which follow, which are accompanied by a drawing in which the single figure represents a circuit arranged according to our invention. I

In the circuit illustrated, according to our invention, a constant non-capacitive resistance is inserted not directly in radio fre- O quency circuits, but in the plate circuit of a tube generator coupled in three-point connection. By means of this resistance, the oscillation power of the tube generator can be regulated at will, and independently of phase relations and conditions. The resistance is chosen just so high that the power of the tube as a generator suliices for reduction of the damping in the oscillation circuits. An incidental advantage of the arrangement is that the plate current is weakened by the ex:

ternal resistance, sothat the electronic current e'mittedby the cathode is of smaller value.

A further merit resides in that, because of the lower energy available in the oscillation circuit resulting oscillations possess relatively small intensity, and what is known as an en training effect is produced when relatively powerful transmitters are received. 1

The disposition of the resistance is so chosen that the energy resulting from the audion' effect causes potential variations across said resistance sothat the damping re sistance serves at the same time as a coupling V resistance for the next tube.

Referring to the drawing, the inductance 22 is variably coupled to the antenna inductance 4. The triode 6 is regeneratively coupled in three point connection to the inductance22, the variablecondensers 8 and 10 serving to tune the circuit and to control the regeneration. The oscillation power of the tube generator may be controlled over a wide range according to the choice of the magnitude of the stabilizing resistance R which, if desired, but not necessarily, may be variable. The resistance is chosen of sutfi cient magnitude so that the oscillation circuit will overcome the'natural damping of these circuits, but without producing oscillation. The resistance R also serves as a resistance coupling for the amplifying tube 12. 14 and 16 are usual grid condensers, and 18 and 20 are usual grid leaks. 'The output of the amplifying tube 12 may be connected to the input of additional stages of amplification, or as shown, may be taken directly to an acoustic unit 22, which is by-passed in the customary manner by a condenser 24.

' We claim:

1. In combination, an electron emission tube having anode and grid circuits includ ing regeneratively coupled inductances, a tuning condenser, a second vacuum tube, a source of anode potential, and a damping resistance in series therewith connected across the input circuit of the second tube and in parallel with the anode inductance of the re- 7 generativ'ely coupled tube.

3. A regenerative receiver comprising an electron emission tube, anode .and control electrode circuits including regeneratively coupled inductances, a tuning condenser, and a seriescombination of a substantially pure ohmic resistance and a source of direct anode potential connected in parallelwith the regeneratively coupled anode inductance.

MANFRED VON ARDENNE. HEINRICH HEINERT. 

